He adds this very good question at the top of the re-post:
In Christ, we are all already part of the new covenant. Because of that covenant we are all now children of God and, therefore, brothers and sisters with one another. That covenant alone covers how we should interact with and treat one another. So, why do so many feel that we still need more covenants, i.e. a church covenant?
I'm not sure what Alan's intended scope is when he refers to "church covenants," but I'm assuming he also means - and if he doesn't mean it, I will add it to the list! - to include church membership covenants. Either way, he hits the nail on the head.
What can an extra-biblical church covenant do that the new covenant cannot? After examining this question in several paragraphs, Alan concludes with:
If we use a “church covenant” to include some believers and exclude others, then we are dividing the body of Christ and making distinctions that only God can make. We are trying to choose who to love and who to serve. (Of course, this makes life much easier, but it doesn’t make it a life that [is] lived according to the gospel.)
I also note here that I have dealt with the same concept in different ways in Part 21 and Part 27 of this series. Please make an effort to read Alan's recent post.
Read the entire series here.